System for controlling the application of power



Oct. 12, 1943. E A. ROCKWELL SYSTEM FOR CONTROLLING THE APPLICATION OF POWER 12 Sheet-Sheet 1 Filed Jan. 4, 1940 ATTO :EY

v INVENTOR w & BY I L Oct. 12, 1943- E. A. ROCKWELL 2,331,800

SYSTEM FOR CONTROLLING THE APPLICATION OF POWER Filed Jan. 4, 1940 12 Sheets-Sheet 2 E. A. ROCKWELL v SYSTEM FOR CONTROLLING THE APPLICATION OF POWER Filed Jan. 4, 1940 12 Sheets-Sheet 3 IQ 1l.9 M

ATTO NEY .GGGGGGGGGGG G G fl 8 G G GEGQ HlllLllllHlM Oct. 12, 1943. ROCKWELL 2,331,800

SYSTEM FOR CONTROLLING THE APPLICATION OF POWER Filed Jan. 4, 1940 12 sheets-sheet 4 \NV NTOR @HMA a 1 BY MW ATJ' NEY 1943- V E. A. ROCKWELL 2,331,800

SYSTEM FOR CONTROLLING THE APPLICATION OF POWER Filed Jan. 4, 1940 12 Sheets-Sheet. 5

" I I Q 1670 16 J m I Z00 9 3 I I I 194 INVENTOR 220mm 0. BY WM ATTO NEY.

Oct. 12, 1 943.

E. A. ROCKWELL 2,331,800

SYSTEM FOR CONTROLLING THE APPLICATION OF POWER Filed Jan. 4, 1940 12 SheetsSheet 6 INVENTQR M a I BY 7 ATTONEY Oct. 12, 1943. E. A. ROCKWELL 2,331,300

SYSTEM FOR CONTROLLING THE APiPLICATION OF POWER Filed Jan. 4, 1940 12 Sheets-Sheet 9 INVENTOR Oct. 12, 1943. E, A. ROCKWELL 2,331,300

SYSTEM FOR CONTROLLING THE APPLICATION OF POWER v I Filed Jan. 4, 1940 12 Sheets-Sheet 1o Z64 m I BY I a he 5 Q Z63 ATT RNEY Oct. 12, 1943- E. A. ROCKWELL 2,331,300

SYSTEM FOR CONTROLLING THE APPLICATION OF POWER Filed Jan. 4, 1940 12 Sheets-:Sheet 11 INVENTOR Y ml a.

' A'ITORNEY.

Oct. 12, 1943. E. A. ROCKWELL v2,331,800

SYSTEM FOR CONTROLLING THE APPLICATION OF POWER Filed Jan. 4, 1940 12 Sheets-Sheet 12 ATTORNEY Patented Oct. 12, 1943 UNITED STATES SYSTEM FOR CONTROLLWG THE APPLICA- TKON OF POWER Application January 4, 1940, Serial No. 312,356

13 Claims. (Cl. Gil-54.5)

My invention relates particularly to an apparatus designed for controlling the application of power for the operation of different parts or accessories of automotive vehicles, as, for example, automobiles, aeroplanes, railroad cars, mine locomotives, etc.

The object of my invention is to provide a system whereby the diiferent parts of automotive vehicles may be operated in an advantageous manner so as to maintain adequate control over the same at all times. Another object is to provide an apparatus of this character, in accordance with which the part to be operated may be moved into position initially by means of a fluid applied at one pressure, and thereafter operated to cause the performance of work by said part by fluid at another pressure, this being accomplished, if desired, by various difierentials between the pressures applied for moving said part and the manual or actuating pressures utilized for controlling the pressures so applied. My invention is adapted to be applied, not only for the operation of heavy-duty parts, as, for instance, on heavy trucks, requiring a considerable volume of pressure fluid for the operation of the same but also for the operation of relatively light parts on aeroplanes and other automotive vehicles, such, for instance, as light trucks, etc. A further object of my invention is to provide an improved form of accumulator for accumulating fluid under a high pressure, and adapted to deliver the fluid there'from at a constant uniform pressure, as desired. Another object is to provide an apparatus by means of which fluid at one pressure may be readily converted so as to supply fluid at a higher or lower pressure. Another object is to provide means whereby a constant regulated pressure may be obtained so as to obtain a fluid having a definite and constant sup-- ply pressure. A further object is to provide an improved form of modulator valve. Still another object is to provide an uriloader valve. Another object is to provide a converter valve. Again, another object is to provide an efiective means for the dual control of any of the operating parts, as, for instance, of an aeroplane, so that thereby a modulated operation manually at all times coordinate with the reaction of the operated part, may be obtained. Further objects of my invention will appear from the detailed description of the same hereinafter.

While my invention is capable of embodiment in many diiferent forms, I have shown only certain embodiments thereof in the accompanying drawings, in whicl1--- Fig. 1 is a diagrammatic elevation of a system made in accordance with my. invention, adapted for heavy duty, involving the application of a modulated low pressure and so as to apply thereafter a modulated high pressure;

Fig. 2 is a vertical section of an accumulator for pressure adapted to be used therewith;

Fig. 3 is an end elevation of the same;

Fig. 4 is a vertical section through the same on line 4-6 of Fig. 2;

Fig. 5 is a vertical section of a pressure converter adapted to be used therewith;

Fig. 6 is an elevation of the same;

Fig. 7 is a plan view of the same;

Fig. 8 is a cross-section of the same taken on line 8-8 of Fig. 5; i

Fig. 9 is a longitudinal section of one of the modulator valves;

Fig. 10 is a vertical section of a converter valve;

Fig. 11 is, a plan view of an upper portion of Fig. 14 is a longitudinal section of a hand control valve used therein;

Figs. 15, 16 and 17 are transverse sections through the same on lines l5-i 5, i6l6 and li-- i;

Fig. 18 is a transverse section of the two-way valve used therein;

Fig. 19 is an elevation of a modified form of the system involving the manual application of high pressure to apply thereby a modulated low and then a high pressure;

Fig. 20 is a plan view of a detail thereof;

Fig. 21 is an elevation of a further modification of the system in which a manual fluid pressure is provided for thereafter applying a modulated higher pressure;

Fig. 22 is a longitudinal section of an unloader valve used therewith;

Fig. 23 is a longitudinal section of the regulator valve used in connection with the form shown in Fig. 19;

Fig. 24 is a transverse section 01 a converter from high to low pressure used in Fig. 19.

Fig. 25 is a modified form of hand actuated modulator valve.

Fig. 26 is a diagrammatic representation of the circuit in Fig. 19; and

Fig. 2'7 is a diagrammatic representation of the circuit shown in Fig. 21.

first to the term of, my invention shown in Fig, 1, a system is provided for first applyin a modulated low pressure and for thereafter controlling the application of a modulated high pressure thereby.

There is provided therein a reservoir gravityfeed tank I having a filler opening 2, an inlet 3 for the returned discharged liquid, which may be a hydraulic brake fluid or any other suitable liq l, and aremovable cylindrical screen filter located over an outlet or supp opening 5 which leads by a pipe 8 to a rotary pump 1 which may, for example, be any desired type of gear pump. This is driven by an electric motor 3.

Pressure liquid is thus supplied from the pump 1 by a pipe 9 to an inlet ill on a pressure accumulator H. The pressure iiuid from the pump 8 is thus received in a chamber l2 in a cylinder l3 so as to force to the left in Fig. 2, a piston it which is mounted by means of a screw 55 on a plunger it between which piston l4 and plunger I8 there is a chevron packing ill, of suitable material. A snap ring stop l8 for the plunger i6 is located at the left of the cylinder l3, which latter is screw-threaded, and provided with a pair oi. ears l9 and secured together with a bolt 2|, for screw-threaded attachment to a spring casing 22. The said plunger I6 rests against the face of a spring retainer plate 23. The spring casing 22 also has a split ring stop [it for the retainer plate 23, which is also provided an internal sleeve 25 to act as a guide for a pinrality of Belleville spring washers 2% which are merely dished rings of spring steei. As shown in the drawings, the said rings 25 are located so that the adjacent rings have their dished portions extending in 'opposite directions, said rings being thus carried in an annular chamber 2'5 between the casing 22 and the guide 25 intervals along the chamber spring washers 26 there are ring-shaped blocks 28 to aid in maintaining the alignment of the spring washers 25. The left end the chamber 21 is closed by a screw-threaded as 29, having a pair of ears 30 and Bi, screw-three d to the spring casing 22 and clamped the. by a bolt 32. Bolted to the left face of the cap a cylindrical switch housing 34. which. extends inwardly within the washers 28, the same having a removable screw-plug to permit access to the switch terminals for leads and 3'1 leading to the switch terminals. A cover plate .38 is bolted to the switch housing 34. In said cover plate 38 there is a sleeve 39 having a screw-threaded cap 40 to hold in place a sleeve which has a screw 42 adapted to be received in a slot 53 in the sleeve 39. Said screw 42 also fastens in position an adjustable switch supporting rod 4e provided with a screw-threaded hole 45 to aid in the removal thereof. Slidably mounted on the rod dd there is a copper plate 46 which operates as a startingswitch in the initial starting or setting of the switch apparatus, said plate 46 being normally held in its farthest position to the 1 light spring 41. The other end of said spring tl abuts against a nut 18 on a sleeve 55 carried on the rod 44, said nut 48 having a washer 5b spacing it from an insulated ring 5i. carried on the sleeve 49 and which supports two rod-shaped terminals 52 and 53 connected to said leads 8? and 38 respectively. The copper plate ibis designed to initially close the circuit manuallybetween the said two rods 52 and 53. The righthand end of the rods 52 and 53 have screw- Between groups or threadedthereto conducting plates 54 and 55 which are designed, in the automatic operation of the apparatus, to close the circuit with a copper disk 55 carried on a circuit-breaker sleeve 51 slidable within the sleeve 49 and normally held toward the right in Fig. 2 by a spring 58 to close the said circuit. It will be noted that the lead 36 is connected to one terminal 59 at one side of the motor 8 and the other lead 31 leads to any suitable source of electrical energy,-as, for example, a battery, not shown,which latter is also connected by a lead 60 to a terminal (ii on said motor. The right-hand end of the rod 44 has a stop 62 cooperating with the interior of a shell 63 which is formed on the end of the circuit-breaker sleeve 51. This shell 63 is'adapted to be moved for the automatic making and breaking of the pumping circuit by a ring 84 mounted on a cylindrical member 65 carrying within the same a snap action circuit breaking member 66, the inner left portion of which rests against a spring housing 51, having a spring Gil within the same carried on the outside of a sleeve 69 which overlies a rod lit, having a headed screw H and a washer lid supporting near one end thereof a washer 12 held in place by a snap ring 12a to retain said spring 58 in place.

The said snap action circuit breaking member cooperates with two bell-crank levers l3 and it having rollers 15 and i6 thereon, which latter are forced against the face of the cylindrical member 65 by springs ll, resting against extensions 18 on arms 19 on which the bell-crank levers and '34 are carried by means of pivots 80. The arm form a part of the switch housing 34. The rod after passing through the snap action member 66, at the right thereof, carries a, spring sleeve 81 having therein a spring 82 supported on a sleeve member 83 around the rod '50, which latter has a shoulder 84 supporting an and washer 85 to act as a retainer for said spring 82, The right-hand end of the rod it has a screw-thread 8B which is secured within the spring retainer plate 23 by means of nuts ill. Notches 88 in the face of the cylindrical member 55 also cooperate with said rollers l5 and 16 so as to retain the pump circuit broken when the pressurediquid line is broken, that is to say when the piston is at the extreme right-hand end of the cylinder I3. However, when the said liquid line is complete and the pump motor has been started manually by moving the copper plate 48 to the right, the pump will be started to supply the pressure liquid therefrom to the cylinder 12 and the piston. it will move to the left, accordingly, until the snap action circuit-breaker 86 breaks; the circuit when the desired pressure has been accumulated, so that, thus, liquid is supplied from the cylinder it through a port 69 and thence through radial ports 99 in a valve sleeve 9! which is normally kept in elevated position by means of spring 92 carried in a cage 83 screw-threaded into the end of the cylinder i3. The lower end of the cage 93 has a slotted opening at to permit removal thereof, the same being covered with a screw-threaded apertured dust cap 85. Above the cage 93 there is a screw sleeve 950, the adjusted position of the sleeve being maintained by a screw 86 cooperating with a series of slots 97 in said sleeve. This adjustment of the sleeve 9511 also permits the tightening of an annular seal 98 located above a washer.

89, the seal 58 being supported on the other lace thereof by a spacing member it which rests against an apertured sleeve i0! within which the valve member 9! slides. A check valve M12 is carried within the valve member 9i and is held on its seat by aspring I83. The pressure liquid which'is thus supplied by the force from the pistop It is discharged past the check valve IE2 and thence to a discharge port Ids leading to a pipe iliii, this discharged pressure being a uniform pressure, preferably of about 500 lbs. per square inch.

Another discharge pipe Q86 conveys the pressure liquid at this same pressure from the discharge port ltd to a fitting It? in the upper end of a low-to-high pressure converter 1%, Fig. 5, which fitting iiil also acts as a guide for a valve stem m9 of a valve Hi3 which is initially in its open position in the first part of the operation of the automotive accessory to be operated by the pressure liquid. This open position oi the valve H8 is insured by a shoulder member iii held in place a snap ring. lilo. on the lower end of said valve, which shoulder member cooperates with the rear face of a plunger H2 secured by screws 8 l3 to a piston lid which operates within a cylinder M5 in the upper part of the low pressure converter 303. A sealing ring H6 is located between the plunger H2 and the piston il i. Thus the lower end of the valve l I6 is adapted to move within a cylindrical chamber I ill within the piston ti l, having a communication port iifla with the cylinder M5, the shoulder member iii being normally held in its upper position by a spring iii? to seat the valve lit and located around a guide-rod H9 screwthreaded within the piston at the lower end thereof. The lower end of said piston lit carries a large piston I20 and a sealing ring l2i which operate within an enlarged cylinder Hi, the lower end of which is closed by a screwthreaded cap I25 having clamping cars 52 1 held together with a bolt I25. A normally closed airbleeder screw A25 is carried in the lower face of the cap L23 and is removable from the screw 526a. having an air escape port H261; to permit the escape or" air. At the upper end of the-enlarged cylinder i722 there are a plurality of breather openings i2'i. Each of these openings i2? carries a screw threaded shell I28 having an air port l2il, said shell being secured by a screwthread and cotter-pin 930 to a cover l3ifilled with horsehair 532 so as to convey the filtered air therethrough to a tube E33 leading to an inlet port and the cylinder 322. The pressure liquid thus passes through the normally open valve MB to an outlet pipe i135 and thence to a high pressure inlet port ltd in a modulator valve having a casing H31. The said modulator valve casing iSl, Fig. 9, has secured to the upper end thereof, by means of a locking screw i38, a pedal bracket I38 provided with a pivot i iu for a foot treadle ldl. The said treadle i il has a boss M2 on the lower face thereof which bears upon a plunger M3 in the pedal bracket I39 and is protected from access of dust by a rubber boot let. The plunger'i l3, when the treadle Edi is depressed, is adapted to move downwardly a rod M5, Fig. 25, having a guide flange it for guiding it in a screw sleeve idl carried in the end of the valve casing 531. On the other side'of said flange M6 there is a plunger idt provided with a seal M9, Fig. 25, supported in a chamber 856 in a part of the screw sleeve iii.

In one form of my invention, Fig; 25, a light spring idi is located within the plunger its and bears at its other end, by means of a rod 151a, against a disk valve 952 which cooperates with a valve seat L53 on the end of a cylindrical modulator valve ltd. The spring l5i keeps the valve disk i52 normally lightly closed to keep air from accumulating to the left of said valvelbi.

Said modulator valve I55, Fig. 9, is slidable within a sleeve 355 having ports 855 communicating with a low pressure outlet port H51 connected by a pipe 958 to the reserve tank 5 by means of the port 3. An annular rubber seal use is provided between the sleeve R55 and the sleeve ldl. Another annular seal its is located on the other side of the sleeve H55 adjacent to a metallic spacing member it i, adjacent to which there is a seal told and a ported sleeve I52 having a seal its communicating with the pressure liquid port i3fi. Adjacent to said seal 563 there is a ported sleeve ltd which leads to a modulated pressure port 655. It will be noted that the spacing member it! has a valve seat let to cooperate with a conical valve itl on the cylindrical valve 5%. Also on the outside of said cylindrical val e I56 there is an annular recess H68 communicating with ports use therein leading to a longitudinal passageway H0 in the said valve iEfl. A strong spring i'il normally moves the cylindrical valve w t to seat the valve 9%! against its seat I66. The disk valve is thus manually movable by the treadle idi so that by first keeping the disk valve iii? closed manually on its seat i253 the cylindrical valve ltd be moved down wardly, in Fig. :9, so as to open communication, past the valve i il, between-the port 5535 and the interior of said valve 55% and thence to the modulated pressure port its. Instead of the pedal iii 1 may use, as in Fig. 25, a hand lever i874; on a pivot Edit, to operate the rod if; having a felt dust cover idle, the lever idle also having a stop arm ilild through which a stop rod idle passes.

The modulated pressure thus passes from the port iEE by a pipe M3 to a tubular T-block ill having one branch H5 leading to the brake actuation apparatus, and which may be comprised of two tubular connections 3'55 and ill leading, respectively, tobrake operating devices H8 and H9. Each of the latter carries a piston 88d, in a cylinder 655, which is connected by a rod id! to the brake shoes in the usual way, the cylinder in or 5T9 being connected with a bracket I83 fastened. to the frame of the automobile. If desired, a further tubular connection BM may branch rearwardly from the tubular connections H6 and Ill, for connecting the same with a trailr, for which purpose there may be a manual shut-oh valve it? having a flexible tubular connectlon its leading to a manual shut-ofl. valve is? which in turn is provided with atubular connection 588 leading to tubular branches E89 and Eat leading, respectively, to brake-operating units 598 and i192 constructed like the brake-operating units i'l-S and lit. V

When the modulated pressure provided through the pipe 813 has moved the brake shoes into their position for applying thereafter the braking force,

the pressure in. the pipe H5 will rise and this pressure takes efiect through a pipe 33 connected to their-block- Hill which leads to a port ltd in a fitting ltd of a converter valve having at the other side thereof a normally closed air bleeder H95, Fig. 10; Within the fitting N5 there is a plunger it? having an annular seal i813 movable within a cylindrical chamber 8%, the other end of which has a screw sleeve 200 to act as an abutment for a spring 20I which normally forces the plunger I91 to the right, in Fig. 10. A rod 20Ia. on the left end of the plunger I91 passes through the screw sleeve 200 and bears on a rod 202 constructed the same and having parts and valve connection the same as the rod I45. This fitting I 95 is secured by screws 203 to a valve casing 204 constructed exactly the same and provided with the same kind of valve as in the valve casing I31 previously described. In this instance the valve within the casing 204 is moved by the pressure accumulated within the pipe I93 so as to keep the said valve open during the continuance of said pressure and thus, at that time, to transmit the pressure fluid received from the pipe I05 through said valve and thence through a pipe 205 to a port 206 in the cap I23 of the lowto-high pressure converter I08.

The low pressure liquid discharged from the valve casing 204 when the high pressure within the pipe I93 ceases, is discharged by a pipe 201 through aport 208 on the inlet side of the pump 1, which is also connected to the pipe 6. In this way, when the pressure in the pipe 205 has been applied, as above referred to, the piston I20 is moved upwardly, thus closing the valve H and the low pressure inlet into the cylinder I08, the construction of the valve IIO being such as to permit an ample flow of liquid past the same when open and so as to avoid wear on the seat for the valve IIO. Thereafter the high pressure liquid produced by the low pressure converter I08 is supplied through the pipe I35 which is then modulated by the modulator valve in the casing I31 and thus delivered as modulated high pressure through the pipes I13 and I15 to the brakes so as to apply this high pressure to secure the braking effect on the brake shoes.

The modification of my invention shown in Fig. 13 is designed for providing a dual alternative control of 'the apparatus. This form of my invention is constructed the same as the form shown in Fig. 1, except in the following respects: In this form of my invention the pipe I35, which provides the pressure fluid to be modulated, leads to a modulator valve 209 which is constructed the same as the modulator valve I31 previously described and having a return or low pressure pipe I58 leading to the reserve tank I. This valve, however, instead has a hand control for operating the plunger I45.

For this purpose, carried on the valve casing 2 there is a bolt 2), Fig. 14, for fastening the hand control casing 2 to the modulator valve casing I31, which casing is tightly fastened in place by ear 2I2 and a bolt 21I3 passing through the same and through a part of the casing I 31. The plunger I45 is operated by a disk 2E4 carried in a sleeve 2 I and having a rod 2I6 thereon extending into a spring 2I1, which is located within the sleeve 2| 5. A rod 2I8 also extends within said spring 2I1 from the other end thereof and has a reduced portion 2I9 extending into a reduced opening at the right end of the sleeve 2I5. Abutting against the right end of the sleeve 2 I5 there is a screw-piece 220 screw-threaded into a high pitch thread 22I within a screw sleeve 222 having an outside screw-thread 222a screwthreaded into the hand control casing 2 I I. The said casing 2 has a radial pin 223 screwthreaded into the same to cooperate with a clip 224 for normally holding the hand control in open or inoperative position. This clip 224 is supported upon a boss 225 on an outer sleeve 226 by livered by a pipe means of screws 221 and 228, the said outer sleeve 226 being fastened to the screw member 220 by means of a screw pin 229. Furthermore, the said sleeve 228 has a hexagonal end 230 onto which there is clamped a handle 23I having ears 232 and 233 through which a bolt 234 passes.

The remaining or brake control port 235 (Fig. 13) is connected by a pipe 236 to a control port in a valve seat fitting 231 of a double check valve casing 238 provided with a reciprocable cylindrical valve member 239. The opposite face of said double check valve 238 is' connected by a port in a valve seat fitting 240 and a'pipe 24I to another manual control, such, for example, as a treadle controlled modulator valve 242 constructed the same as the modulator valve I31, for

pedal operation. This valve may have a low pressure connection 242a leading to the pipe I58 and a high pressure connection 24% leading to the pipe I35. The said double check valve thus having the two ports 231 and 240, which may be alternately closed by either one or two pilots by means of the valve member 239, is adapted thereby to deliver the modulated fluid pressure by the pipe I 13 for controlling any desired part of an aeroplane.

It will be noted that the said reciprocable valve member 239 may be provided with a lateral passageway 240 (Fig. 18) to permit the passage of liquid in either direction so as to reach the outlet pipe I13, and that opposite to the latter pipe there may be a screw-plug 245 for giving access to said valve 239. Ears 246 and 241 are provided on the valve casing 238 to permit the attachment thereof to any desired part of an aeroplane.

The modification of my invention shown in Figs. 19 and 20 is designed for heavy-duty operation and may be used, for example, in connection with the operation of mine locomotives or railway cars. This modification of my invention is designed, furthermore, to modulate a regulated high pressure to produce a modulated low pressure for bringing the brakes into position preparatory to applying the braking force and thereafter to apply a modulated high pressure to said brakes for obtaining the braking force. In this form of my invention I have provided the same type of reserve tank I having the outlet port 5 leading to the supply pipe 6. This supply pipe 6 communicates with a spill-back tank 248 which has a vent pipe 249 leading up, through the tank I beneath the cap 2 thereon. The vent pipe 249 opens from the top of the spill-back tank 248. The pipe 6, however, continues inwardly into the latter to communicate with the inlet side of a rotary pump 250 which may be a gear pump and which is driven by an electric motor 25I. This pump 250 is connected so as to deliver, by a port, the high pressure liquid to an accumulator 253 constructed with the same parts as described in connection with the accumulator II, in Fig. 1, and has the same circuit connections to the electric motor as there described, except that a pressure of about 1500 lbs. per sqare inch is capable of being supplied thereby. The high pressure liquid thus accumulated in the accumulator 253 is de- 254 from a passageway 254a therein having a check valve 254b, to a regulator valve 255 for maintaining a definite pressure, which has a valve structure exactly the same as in the valve I31 except that in this instance the plunger I45 is operated by a disk 251 (Figs. 23 and 26) having a knob 258 supported on a guide disk 259 in a spring housing 260 which has a spring 260a bearing upon the presser plate 261.

The spring housing 260 is carried in an arm 262 held by ears 263 through which a pivot 266 passes to hold it onto the valve housing I31 with the aid of a stop pin 266a cooperating with an apertured extension 26% on the arm 262. This regulator valve 255 is connected by a port 265 to the pipe 256 from which the valve receives the pressure liquid delivered by the accumulator 253. The low pressure, or exhaust liquid, leaves the valve 255 by a pipe 266 to return to the spill-back tank 268. In this valve structure the valve I52, I53 is normally closed by the spring 260a and the valve I66, I68 normally open and the compression of the spring 2600 normally maintains the pressure of the liquid at a given desired pressure. When this pressure is exceeded the said two valves open and close, respectively, and the exhaust liquid passes out by the valve I52, I53. This construction produces a regulated pressure of approximately 1000 lbs. 'per square inch, which is delivered by the said valve 255 through a port 261 to a pipe 266 which then conveys it to a high pressure port 269 of a modulator valve 210, and which is constructed the same as the modulator valve I31 except in this instance the spring II and plunger I5Ia are omitted and inside the spring I there is a light spring 21Ia (Fig. 9) to normally keep the valve I52 open. It is to be understood, also, that this form of the manual actuator with the spring 21 la can be used with the treadle I6! instead of the spring I5I and spring I5Ia. On the side of said modulator valve 210 the pipe 268 has a connection which conveys the high pressure liquid by a-pipe 212 to the high pressure port 213 of a hand-operated modulator valve 216 provided with a discharge pipe 216a leading to the reserve tank I, and having a handle 215 tooperate the same, all of which is constructed exactly like the modulator valve I31 together with the hand control as shown in Fig. 14. This handle 215 thus enables modulated high pressure to be delivered from a port 216 thereof by a pipe 211 to a delayed-action hydraulic modulator controlling device 218 constructed like the hydraulic operating element in Fig. 10 except that there is a strong spring I therein which operates thesaid modulator valve 210 hydraulically according to the operation of the hand lever 215, but only after the brake shoes have been moved up into position. Thus, after the brakes have been moved up into braking position by a supply of modulatedJow pressure liquid thereto, as hereinafter described, the modulated high pressure liquid is dischargedby the modulator valve 210 from a port 219 and thence by a pipe 280 to a brake operating mechanism connected to a'pipe joint 26I the same as the brake operating mechanism shown in Fig. l, to thus apply high pressure liquid for the braking effect. While the modulated high pressure liquid is thus delivered by the pipe 211 to the hydraulic element 218, a portion of this same liquid from the pipe 211, for preliminarily moving the brakes into position, passes by a pipe 282 to a hydraulic device 283 constrcted the same as the device 218 except that in this instance a light spring 20I is used, and which in turn operates a modulator valve 286 constructed the same as the modulator valves previously described, as, for instance, the modulator valve I31. In this instance the high pres sure liquid to be modulated by the hydraulicelement 283 is received by a pipe 285 from the other side of the accumulator 253 and is thus received in a high pressure port 286 of the modulator valve 236 from which the modulated pressure liquid is delivered by a pipe 261 to the high pressure side of a high-to-low pressure converter 288. This is comprised of a small cylinder 288a, having a normally closed air bleeder 288b, in which there is a piston 2880 with a check valve 208d. The check valve 28812 is in a passageway 288a leading to a low pressure large cylinder 288i, having a piston 2889, and provided with an air bleeder 26611.. An air filter 288i is'on the cylinder 286i, constructed like the air filter I28. The said modulator valve 286 is provided with a discharge or exhaust port 2887' leading back to the spill-back tank 268, The low pressure side of the said low pressure converter 288 is connected by a pipe 266 to a low pressure port 290 in the modulator valve 210. This low pressure supplied through the port 290, due to the strong spring 2M keeping the valve I52 open in the initial operation of the brakes, permits the low pressure fluid to pass between the valve I52 and its seat and thence to the pipe 280 for the movement of the brake shoes up to the braking position. When the pressure in the pipe 280 has been applied to such an extent as to move the brake shoes into position, the increase in pressure within the pipe 211 will seat the valve 552 in the modulator valve 210 to permit the entry of high pressure liquid by the valve I61, thus supplying the high pressure liquid through the pipe 200 to apply the braking effect as previously described. The exhaust flow of liquid from the modulator valve 210 is received in the pipe 209. In this way a relatively high pressure may be used for applying a comparatively low pressure for the initial setting of the brakes, as, for instance, on mine locomotives or railway cars, while high pressure liquid is applied thereafter to the brakes to obtain the desired brakin force.

In the form of my invention as shown in Figs. 21 and 22 I have provided a similar system for controlling the operation of the parts of automotive vehicles and which is designed for installation on units involving heavy duty. In this instance means is provided for initially moving the parts into position by merely a manual force applied hydraulically after whih a high pressure liquid is brought into action thereby to apply the braking force. In this instance a foot pedal 29I is pressed to the left in Fig. 21 to operate a rod 292 attached to a piston 263 in a master cylinder 296 having an inlet port 295 for liquid from a supply tank 296. The forward movement to the left, in Fig. 21, of the piston 233 will force the liquid out of the cylinder 296 into a pipe 201 and thence to a pipe 296 into a low pressure port 299 on a hydraulic operating unit and modulator valve 300, which is constructed the same as the modulator valve 210, so that the liquid initially passes from the pipe 268 by the valve I52 through the tubular valve i513 and thence to a port 30! and a pipe 302 to a brake-operating cylinder 303 for moving the brake shoes 306 and 305 into position. This movement of the liquid under manual pressure will continue until the brake shoes 306 and 305 are moved entirely into position, after which the pressure in the pipe 302 will increase to such an extent that the liquid from the pipe 291 will operate a hydraulic unit 306 which is constructed the same as the hydraulic unit 210} and thereby operate the tubular valve in the modulator valve 300 so as to cut oil! the entry of liquid from the pipe 298 while modulated high high pressure liquid is delivered to the modulator valve 300 through a port 301 from a pipe 303 and is supplied to said pipe from a port 309 in a regulator pressure valve 3"). constructed the' same as the regulator pressure valve 255. The exhaust or low pressure from the regulator valve 3| passes out by a low pressure port 3| I to a tank 3I2. Furthermore, the high pressure liquid is supplied to said regulator valve 3I0 by a port 3I3 from a check valve controlled port 3 which is connected to the discharge side of an accumulator 3I5 constructed the same as the accumulator II previously described, and the liquid under pressure is supplied to said accumulator 3I5 by means of a rotary pump 3I6 located in the tank H2 and driven by an electric motor 3I1, the said motor and pump being constructed and arranged the same as the motor 25I and the pump 250 in Fig. 20. The same type of electric circuit is used thereon as previously described. In the return movement of the pedal 29I, means is provided for unloading the manual pressure liquid in the pipe 291 quickly, to provide uniformity of action at all times, by means of a branch pipe 3I3 which is connected to an unloader valve casing 3I9 the valve in which is opened automatically by a bell crank lever 320 pivoted on cars 32I on the valve casing 3I9, the lower end of the bell crank lever 320 being connected by a cable 322 to an arm 323 held in place by nuts 324 on the rod 292. The unloader valve within the casing 3I9 is comprised of a fitting 325 (Fig. 22) communicating with the pipe 3I8, which fitting is screw-threaded in the casing 3I9. The said fitting 325 supports a spring 323 to hold upwardly a valve 321 against a seat 323 within said casing 3I9. A chamber 329 is provided, in which the valve 321 moves and when the said valve is unseated it communicates with a chamber 333 leading by a passageway 33I to a port 332 and a pipe 333 fastened to a fitting 334 which communicates with the upper portion of the tank 293. A filler cap 335 is also provided on the top of said tank 296. By this means, when the foot is taken off the pedal 29I- the liquid in the pipe 291 is automatically unloaded quickly into the tank 296 In the operation of my invention as shown in Fig. 1, when it is desired to put on the brakes or operate any other part of the automotive vehicle the pedal I is moved downwardly and the relatively low pressure liquid received through the port I36, due to the closure of the valve I52, is allowed to pass by the valve I61 in modulated amounts, thence through the port I83 and out through the port I55 to the pipes I13 and I15 and then to the brakes to initially move the brake shoes into position. When the pressure in these pipes accumulates to a higher pressure, this pressure reacts through the pipe I93 on to the converter valve 204 to keep the said valve open while this high pressure condition continues, the result 01' which is to cause the low pressure liquid received. by said valve 204 from the pipe I05 to pass by the pipe 205 to the low-- to-high pressure or large cylinder end of the low pressure converter I03, thereby closing the valve .III and placing the liquid under high pressure in the cylinder H5, which is then discharged by the pipe I35 to be modulated by the modulator valve I31 and thence delivered in the form of high pressure by the pipes I13 and I15 to the brake shoes for producing the braking eii'ect thereon. This braking pressure can be modulated. that is to say increased or decreased at will, according to the increments or partial release of the liquid in the pipes I 13 and I15 by the valve I31. Upon the release of the pedal I the parts are restored to their initial positions, the exhaust liquid passing by the pipe I53 to the reserve tank I and from the valve 204 by the pipe 201 to the low pressure side of the pump 1. Throughout the operation, as described above, the accumulator II will maintain therein a body of liquid under the minimum desired pressure, which may be approximately 1000 lbs. per square inch, ready to be utilized whenever desired upon the actuation of the pedal I. By this means a relatively low pressure is provided for initially setting the brakes, followed by modulated high pressure for applying the braking force. Also, if desired, the brakes can be operated by the manual force through the continuous body of the hydraulic fluid to the brakes in case of failure of the other liquid pressures.

In the form of my invention shown In' Fig. 13, the operation of the parts is the same as in Fig. 1 except in this instance a dual alternative control is provided, which is, for example, very useful in connection with aeroplanes. In this instance, in otherwords, the hand-controlled modulator valve 209 or the pedal controlled modulator valve 242 may be utilized, as, for example, by either one of two pilots operating the aero-.

plane. According to which one of these manual controls is being used, the double check valve 233 will automatically be moved to permit the operation from either of said controls.

In the form of my invention shown in Figs. 19 and 20, there is utilized a relatively high pressure which initially brings a relatively low pressure into action for setting the brakes into position, after which a modulated high pressure is applied for applying the braking force. In this instance, when the hand control modulator valve 214 is operated the high pressure liquid received by said valve from the pipe 212 is applied through the pipe 282 to the light spring hydraulic control 233 so as to modulatingly release the high pressure fluid received from the pipe 285 through the pipe 231 to the high pressure end of the high-to-low pressure converter 233 so as to thereby force out of the low pressure side of the same, through the pipe 239, a low pressure liquid which passes directly through the modulator valve 210 because the valve I52 is kept open .at this stage by the strong spring control 213, 20I this low pressure liquid being thus delivered by .the pipe 230 to the brakes to move the brake shoes initially into position. As the pressure applied increases in the pipe 211 this brings about no increased action on the part of the control 233 btu acts to overcome the strong spring 20I in the control 213, thus closing the valve I52 and opening the valve I51 in the modulator valve 210, and thus supplying a modulated,

2337 back to the spill-back tank 243.

In the form of my invention shown in Fig. 21. manual pressure is utilized for bringing the brake shoes into position, after which a high pressure is brought into action for applying the braking force to the brakes. For thispurpose, when the foot pedal 29! is manually operated the piston 293 traps some of the liquid received from the port 295 and then. forces the same through the pipe 29'! and'the pipe 298 past the open valve I52 and through the pipe 302 to move the brake shoes 304 and 305 into position. As the pressure of this liquid increases, the hydraulic unit 306 isoperated to close the valve 32, thus unseating the valve I61 and admitting high pressure liquid received from the accumulator 3l5 to the pipe 302 for applying the force of the high pressure liquid so as to obtain the desired braking eiTect upon the braking shoes. This high pressure liquid, by means-or the valve I52 in the desired increments, enables the modulated pressure to be utilized in the on or oii" modulation so as to obtain a carefully and exactly modulated brakin efi'ect, that-is to say a braking efifect which is accurately coordinatedto the manual force applied to the manual actuating means, the same as in the case of the other forms of my invention above described. Upon the release of the manual pressure the liquid fiows in the reverse direction through the pipes 3132, 298 and 291, and, due to the unloader valve 319, is discharged quickly through the passageway 332 into the supply tank 296 ready to be used again in the same way when the manual force is again applied to the pedal 29!. This unloader valve is quite similar inoperation to the low-to-high pressure converter valve operation H0, especially because of the lost-motion connection to said valves.

While I have described my invention above in detail I wish it to be understood that many changes may be made therein without departing from the spirit of the same.

I claim:

1. In combination, hydraulic means, including a pressure-reactive hydraulically operating valve, adapted to exert a pressure varying at will for the actuation of a, part by a hydraulic pressure liquid, means, including an accumulator-reservoir having an intermittently operating charging means controlled by the pressure from the accumulator, for supplying said hydraulic liquid under a substantially constant .predetermined superatmospheric pressure to said hydraulic means, a high-to-low pressure converter means operated by pressure liquid controlled by the operating-valve, said converter including a plunger through which pressure liquid is released, and a valve, acting by means of the pressure of said first mentioned hydraulic pressure liquid conveyed from the first mentioned valve to operate the converter, so constructed as to control the exertion of another pressure on said part through said supplied hydraulic liquid upon the application of pressure to the second mentioned valve.

2. In combination, hydraulic means, including a manually movable pressure-reactive hydraulically operating modulating valve, adapted to exert a pressure varying 'at will for the actuation of a part by a hydraulic pressure liquid, means, including an accumulator-reservoir having an intermittently operating charging means controlled by the pressure from the accumulator, for supplying said hydraulic liquid under a substantially constant predetermined superatmos-.

.pheric pressure to said hydraulic means, and a high-to-low pressure converter means operated by pressure liquid controlled by the operating valve, said converter including a plunger through which pressure liquid i released, and a valve,

acting by means of the pressure of said first mentioned hydraulic pressure liquid conveyed from the first mentioned valve to operate the converter, so constructed as to control the exertion of another pressure on said part through said supplied hydraulic liquid upon the applicaliquid controlled by the operating valve,said converter including a plunger through which pressure liquid is released, and a valve, acting by means of the pressure of said first mentioned hydraulic pressure liquid conveyed from the first mentioned valve to operate the converter, so constructed as to control the exertion of another higher -pressure on said part through said supplied hydraulic liquid.

4. In combination, hydraulic means, including .a manually movable pressure-reactive hydraulically operating modulating valve, adapted to exert a pressure varying at will for the actuation of apart by a hydraulic pressure liquid, means, including an accumulator-reservoir having an intermittently operating charging means controlled by the pressure from the accumulator,

for supplying said hydraulic liquid under a. pre-* determined superatmospheric pressure to said hydraulic means, and a high-to-low pressureconverter means operated by pressure liquid controlled by the operating valve, said converter including a plunger through which pressure liquid is released, and a valve, acting by means or the pressure of said first mentioned hydraulic pressure liquid conveyed from the first mentioned valve to operate the converter, so constructed as to control the exertion of another higher pressure on .said part through said supplied hydraulic liquid by the manual modulation of said supplied pressure liquid.

5. In combination, hydraulic means including a pressure-reactive hydraulically operating valve adapted to exert a pressure varying at will for the actuation of a part by a hydraulic pressure liquid, means, including an accumulator, for supplying said hydraulic liquid under a substantially constant predetermined superatmospherio pressure to said hydraulic means, and operating means, including a valve device through which operating means the liquid'from the first mentioned valve is adapted to pass and a high-to-low pressure converter receiving liquid controlled from the first mentioned valve, having a piston through which pressure liquid is released, said operating means acting by means of the pressure in the converter, and being so constructed as to exert another pressure on said part through the hydraulic liquid from said second valve device.

6. In combination, manual hydraulic means including a pressure-reactive hydraulically operating valve adapted to exert a pressure varying at will for the actuation of a part by a hydraulic pressure liquid, means, including an accumulator,

for supplying said hydraulic liquid wider. a subetantialiy constant predetermined superatmospherlc pressure to said hydraulic means, and operating means, including a valv device through which operating means the liquid from the first mentioned valve is adapted to pass, and a high-to-low pressure converter receiving liquid controlled from the first mentioned valve, having a piston and valve through which pressure liquid is released, said operating means acting by means of the pressure in the converter, and being so constructed as to exert another pressure on said part through the hydraulic liquid by the -manual modulation of the pressure liquid from said second valve device.

7. In combination, hydraulic means, including a pressure-reactive hydraulically operating manually controlled modulating valve adapted to produce one pressure for moving an automotive vehicle brake by a hydraulic pressure liquid, means for supplying said hydraulic liquid under a substantially uniform super-atmospheric pressure to said hydraulic means, and a high-to-low pressure converter means having a piston through which pressure liquid is released and operating means including a valve device through which operating means the liquid from the first mentioned valve is adapted to pass, and being so constructed as to exert another pressure on said automotive vehicle brake upon the application of pressure to the second mentioned valve device.

8. In combination, an accumulator for accumulating a hydraulic pressure liquid under a superatmospheric pressure, a high to low pressure transformer supplied with pressure liquid therefrom, a valve for modulating said accumulated hydraulic liquid to the transformer, which is transformed to a lower-pressure liquid therefrom for moving a part by the latter, and a valve operated by an increase of the pressure in said supplied liquid to produce another movement of said part by the modulation of said accumulated hydraulic liquid, said last mentioned valve having its liquid release passing through said transformer to the accumulator.

9,. In combination, an accumulator for accumulating a hydraulic pressure liquid under a substantially uniform superatmospheric pressure, a high to low pressure transformer supplied with pressure liquid therefrom, a manually controlled valve for modulating said accumulated hydraulic liquid to the transformer, which is transformed to a lower-pressure liquid therefrom for moving a part by the latter, and a valve operated by an increase of the ressure in said supplied liquid to produce another movement of said part by the modulation of said accumulated hydraulic liquid, said last mentioned valve having its liquid re lease passing through sald transformer to the accumulator.

10. In combination, a reservoir, an accumulator for accumulating from the reservoir a hydraulic pressure liquid under a superatmospheric pressure, a high to low pressure transformer supplied with pressure liquid therefrom, a valve for tioned valve back to the reservoir.

11. In combination, a reservoir, an accumulator for accumulating from the reservoir a hydraulic pressure liquid under a substantially uniform superatmospheric pressure, a high td low pressure transformer supplied with pressure liquid therefrom, a manually controlled valve for modulating said accumulated hydraulic liquid to the transformer, which is transformed to a lower-pressure liquid therefrom for moving a part by the latter, and a valve operated by an increase of the pressure in said supplied liquid to produce another movement of said part by modulating said accumulated hydraulic liquid, said last mentioned valve having its liquid release passing through said transformer to the first; mentioned valve back to the reservoir.

12. In combination, an accumulator for accumulating a hydraulic pressure liquid under a superatmospheric pressure, a high to low pressure transformer supplied with pressure liquid therefrom, a valve for modulating said accumulated hydraulic liquid to the transformer, which is transformed to a lower-pressure liquid therefrom for moving a. brake motor by the latter, a valve operated by an increase of the pressure in said supplied liquid to produce another movement of said brake motor by the modulation of said accumulated hydraulic liquid, said last mentioned valve having the liquid release passing through said transformer to the first mentioned valve, and hydraulic connections leading to the accumulator, between the accumulator and the transformer and from the last mentioned valve to said brake motor.

13. In combination, an accumulator for accumulating a hydraulic pressure liquid under a substantially uniform superatmospheric pressure, a high to low pressure transformer supplied with pressure liquid'therefrom, a manually controlled valve for modulating said accumulated hydraulic liquid to the transformer, which is transformed to a lower-pressure liquid therefrom for moving a brake motor by the latter, a valve operated by an increase of the pressure in said supplied liquid to produce another movement of said brake motor by the modulation of said accumulated hydraulic liquid, said last mentioned valve having the liquid release passing through said transformer to the first mentioned valve, and hydraulic connections leading to the accumulator, between the accumulator and the transformer and from the last mentioned valve to said brake motor.

EDWARD A. ROCKWELL. 

